With the increased usage of fluid and fluid systems, a simple and inexpensive leak detection means is not only desirable from the standpoint of economy, but also as sound safety practice. The foregoing is particularly true in the recreational and low-cost housing fields such as mobile homes, trailers, campers and boats which utilize butane or propane gas systems. Accordingly, timely detection of leaks in the conduits or appliances thereof can prevent hazardous conditions which may result in explosions. Heretofore, however, leak detection devices for fluid systems have either been nonexistent, complicated or expensive. The leak detection valve assembly of the instant invention eliminates the foregoing problems by providing a simple and effective, but inexpensive device for determining the existence of leaks in a fluid system.